1ty.me - If you need to send a password or some other form of simple but sensitive information to someone...
sup3rS3cretMes5age - A safe, simple tool for one-time (self-destructing) messages
This Link Will Self-Destruct - This link will self destruct (TLWSD) allows you to create and share links that self-destruct after a set number of views, or at a point in time.
BURN.link - Send secure, encrypted, self-destructing messages
Listiee - Platform for sharing lists & well categorized links
Boop - A scriptable scratchpad for developers. Free & open source!